Abstract
The tumor suppressor gene p53 is important in cell cycle regulation and induction of apoptosis. Accumulation of p53 protein due to mutation of the p53 gene has been shown to enhance chemoresistance in various malignant tumors. This study was performed to clarify whether p53 expression correlates with response to chemotherapy in oral squamous cell carcinoma (OSCC). We retrospectively reviewed 26 cases of OSCC treated with chemotherapy using a combination of cisplatin and 5-FU (CF therapy). Expression of p53 was examined in pretreatment biopsy specimens using the streptoavidin-biotin peroxidase method with antigen retrieval. The p53-labeling index (LI) was 28.64 ± 34.97% (range 0-100%) in patients for whom therapy was effective, and 74.13 ± 35.68% (range 0-100%) in patients for whom therapy was ineffective. The difference in p53-LI values between the two groups was significant (p<0.021, Mann-Whitney U test). Thus, p53 expression was associated with sensitivity of OSCC to CF therapy.
